The present invention generally relates to the transportation and storage container. More particularly, the invention relates to a transportation and storage container for bulk fluid materials in which an inner tank can be removed from an outer shell thereby allowing the shell to be easily shipped back to the initial supplier for reuse.
Numerous industries require that bulk quantities of fluid materials, such as liquids, be easily transported and stored. While a variety of large containers are presently used, perhaps the most common continues to be the conventional fifty-five gallon drum. Notwithstanding its popularity, the fifty-five gallon drum is known to have several significant limitations. The most obvious of these deficiencies include their inefficient use of storage space, their inefficient use of transportation space, awkward handling, problems with complete discharge of the drum's contents, and numerous disposal problems associated with empty drums.
In recent years, the cubic shaped transportation container has seen significant gains in popularity. One variety of this type of container includes a metal outer container having an inner polyethylene tank. While demonstrating numerous advantages in terms of ease of use, storage and transportation, the cubic shipping container has exhibited some drawbacks. For example, when the container is reused and returned to the supplier, a large amount of transportation space is "wasted" because of the overall bulk of the empty container. If recycling of the container is desired, separation of the inner plastic tank from the outer metal shell is often difficult.
An alternative and recent development in bulk liquid shipping containers is the disposable shipping container. One such shipping container is disclosed in U.S. Pat. No. 4,793,519, which is assigned to the assignee of the present application. The container of the referenced patent consists of a rectangularly shaped outer container, formed of a corrugated paper material, in which is housed a thin walled, unitary, blow molded plastic inner tank. Constructed in this manner, the outer container structurally supports and maintains the rectangular shape of the inner plastic tank when filled. Although less expensive to produce than the previously mentioned metal shell containers, the corrugated container is strong enough to permit shipping and stacking. Upon being emptied, the paper material making up the outer container is readily separated from the inner tank for disposal and recycling purposes. While both disposable and recyclable, in a long term continuous supply arrangement, the disposability and/or recyclability of the corrugated paper shipping container may not be the most financially beneficial type of container.
A result of this has been the development of reusable, one-way liquid shipping containers. These containers are shipped are filled and from the liquid distributor or supplier to the various end users. Once the liquids have been consumed and emptied from the containers, at least a portion of the container is returned to the liquid supplier for refilling and subsequent use.
One example of a reusable, one-way shipping container is disclosed in U.S. Pat. No. 5,002,194. This patent is also commonly assigned to the assignee of the present invention and is herein incorporated by reference. The shipping container disclosed in the '194 patent includes a rectangularly shaped, wire mesh outer container in which is housed a unitary, blow molded, plastic inner tank. After complete discharge of the contents from the container's inner tank, the top wall of the outer container is completely removed from the side walls of the outer container allowing the collapsed inner tank to be removed. The removed inner tank may then be either discarded or recycled, which ever is most cost advantageous to the end user. With the inner tank removed, the outer tank is capable of being folded upon itself so that transportation space during its return to the original supplier for subsequent reuse is maximized. Once received by the original supplier, the outer container is unfolded, a new inner tank is placed therein and the container is refilled and reshipped.
While the above reusable shipping container has met with considerable market success, it has been found that the necessity of removing the top wall to permit withdrawal of the inner tank and folding of the outer container, and then reattaching the top wall prior to shipping the collapsed container back to the liquid distributor, tends to be a time consuming process.
In view of the above and other limitations, it is an object of the present invention to provide a reusable container for use in the one-way shipment of bulk liquid materials.
It is also an object of this invention to provide a reusable, one-way bulk liquid shipping container that is durable, yet inexpensive to construct.
A further object of this invention is to provide a reusable, one-way bulk liquid shipping container which is capable of efficiently occupying a minimum amount of space during subsequent return to the liquid supplier.
Still another object of this invention is to provide a reusable, one-way bulk liquid shipping container which readily allows its inner tank to be removed therefrom for recycling or disposal purposes.
In achieving the above and other objects, the present invention provides for a shipping container in which a unitary, blow molded, synthetic resin or plastic inner tank is positioned inside of a wire mesh outer container or shell. The outer container includes a bottom wall, upright side walls and a top. The inner tank can be self-supportive or can have side walls which are substantially thin and thus prevented from being self-supportive. In the latter case, the side walls of the outer container are constructed of a sufficient gauge to structurally support the inner tank when it is located therein and filled with a liquid. The inner tank is also equipped with an inlet fitting and a discharge fitting which respectively extend into fill and discharge openings defined in the walls of the outer container.
The top wall of the outer container is provided in a manner which readily allows the inner tank to be removed once empty. More specifically, the top wall of the outer container includes a pair of panels which are rotatably secured to opposing side walls of the container. The panels are movable from a substantially horizontal or closed position where they overlap one another and extend across the top of the inner container to an open position where they allow the inner tank to be removed. The panels are secured to one another by a latch and pin mechanism that prevents them from being inadvertently opened.
Once the contents of the inner tank have been emptied and it is desired to ship the outer container back to the liquid supplier, the pin and latch mechanism are easily disengaged and the two panels moved to a substantially upright or open position. In this position, the inner container is easily removed up through the top opening defined between the side walls of the outer container. With the inner tank removed, the outer tank is capable of being folded upon itself into a substantially flat and reduce height condition. This condition maximizes transportation space during its return to the liquid supplier.
Additional benefits and advantages of the present invention will become apparent to those skilled in the art to which the present invention relates from the subsequent description of the preferred embodiment and the appended claims, taken in conjunction with the accompanying drawings.